Cocking mechanism for double barrel upward tilting breech firearms



June 9, 1953 D. s. FOOTE ETAL COCKlNG MECHANISM FOR DOUBLE BARREL UPWARD TILTING BREECH FIREARMS 2 Sheets-Sheet 1 Filed Sept. 13, 1949 P N\ n N a a ww m w wwwmm v Q an R. m ww N .Qw mw k R mw mQ wx N T m ml; F 7 c 3 e \l a .6 I I! i 93 a 2. a.-- r :R: nmw I Y .2 a. Q. n Y mN mm. MM 2? \M. m\ h Q\ NM. hm v M. k M. W\

June 9, 1953 v D. s. FOOTE ETAL cocxmc MECHANISM FOR DOUBLE BARREL UPWARD TILTING BREECH FIREARMS Filed Sept. 13, 1949 2 She etsSheet 2 Qls 84 Big 4 'arro//v is L 3 B M [M7 m V85 M06 MN MW 05 Patented June 9, 1953 COOKING MECHANISM FOR DOUBLE BAR- REL UPWARD TILTING BREECH FIREARMS Donald S. Foote and Eugene S. Atwell, Ilion, N. Y., assignors to Remington Arms Company, Inc., Bridgeport, Conn., a corporation of Delaware Application September 13, 1949, Serial No. 115,344

3 Claims. l l 1 This invention relates to a firearm of the upward tilting breech type, particularly illustrate ed by the showing of a side by side double barreled shotgun, although many of its features would be applicable to an over and under type ofshotgun or to double rifles.

The conventional method of constructing this type of firearm unites two rough machined barrels with soft solder and then mills and hand draw files these members to the desired final shape and high degree of finish. The direct labor cost of such procedure is obviously extremely high and the end result not all that could be desired in terms of strength, and of symmetry of those sections subject to expansion and contraction as a function of the heat of firing, etc. The prior art arms of thi class have also been characterized by single trigger mechanisms of such complexity as to virtually defy understanding and by confusing and complex systems of selective automatic ejection.

The prime object of this invention is the production of a firearm of this type of improved quality and. one which utilizes in its manufacture an absolute minimum of hand operations.

Other objectives, largely achieved as an incident to, clean production design, are ruggedness, dependability, and fool-proof operation.

It is contemplated that these objectives and others maybe attained by. the use of barrels which are finish turned to their final dimensions and united to each other only at the breech end.

The barrels appear to be joined to each other and a sighting rib is provided .by the interposition between the barrels of an appropriately shaped bar which may conveniently be of extruded aluminum. The fire control is greatly simplified through utilization of a member attached to and moving with the strikers to positively shift a laterally swingable tri-pper and transfer trigger control from one barrel to the other each time a shell is fired. The selective automatic ejectors employed, while conventional in some respects, are unusual in that they may be said to be gas actuated and are set to eject an empty shell as a function of the chambe pressure as the shell is fired.

The exact nature of the invention as well as other objects and advantages thereof will more fully appear from consideration of the following specification referring to the attached drawing, in which:

i Fig. 1 is a longitudinal sectional view of an assembled shotgun.

Fig. 2 is a side elevation of the barrel assembly.

2 Fig. 3 is a breech end elevation of the barrel assembly.

'Fig. 4 is a transverse sectional view taken on the line 44 of Fig. 1.

Fig. 5 is a transverse sectional View taken on the line 5--5 of Fig. 1.

Fig. 6. is a partial longitudinal sectional view taken on the plane designated as 8-6 in Fig. 4.

Fig. '7 is a transverse sectional view taken on the line 1-! of Fig. 1.

General description cured to the tang by the usual stock bolt. In

the top strap 8 of the tang there are mounted the slidable safety control 9 and the top lever H] which controls the breech locking bolt II. A trigger guard 12 is mounted on the bottom strap l3 of the tang and a trigger l4 and selector l5 extend through the tang into the space within the guard. The major portion of the fire control mechanism, to be more fully described in a later section of this specification, is either mounted directly on or guided by the mounting block l6 which extends between the top and bottom straps of the tang.

As previously noted, the joint pin 5 is mounted in the forward extension 4 of the frame. Arcuate, forwardly facing surfaces H on the barrel lug I8 interengage with rearwardly facing surfaces on the joint pin to provide for the hinged barrel mounting typical of the upward tilting breech actions. A forwardly extending arm IS on the barrel lug 18 extends beyond the joint pin and supports a joint adjusting screw 20 and a fore-end retaining plunger 2|. A wooden foreend -22 is provided with a metallic fore-end base 23 which is arranged to engage the arcuate forwardly facing end of the frame extension 4 in concentric relation to the joint pin 5. The foreend base is maintained in tight engagement therewith by contact with the head of the joint adjusting screw 20 and by the action of the foreend retaining plunger 21 which releasably seats in a fore-end retaining button 24.

The barrel lug'l8 is formed to define a pair of opposed arcuate barrel receiving recesses 25 Within which the finish turned barrels 26 are received and secured as by a furnace brazing operation. The breech end of the barrel assembly is faced off to engage the standing breech 2 when the breech locking bolt I I is engaged in the recess 27 in the barrel lug l8.

The space between the barrels is filled out and a sighting rib is provided by the use of a bar 28 conveniently of extruded aluminum having generally the cross-section of a conventional I-beam. This beam is insertedbetween the barrels in an interference fit with thetop flange 29 and bottom flange 3i engaging the arcuate exterior surfaces of the barrels. At the rear end of the bar the web 3: and bottom "flange 30 are cut away and the upper flangeZQ carried on above the barrel lug. Conveniently, a lug '32 may be received in a recess 33 in the barrel lug and the assembly maintained by the use of a barrel rib retaining screw 34.

Fire control Aspreviously pointed out, -al1-of the firecontrol mechanism is housed between the rearwardly extending straps I8 "and [3 of "the tang of the frame and the components are largelymounted on orguided by th'emountingzblock it. These components include a pair-of main spring plungers '35and 36, each guided for reciprocation in the mounting block [6. Engaged-between the main spring retaining capsB'l and a similar cap (not shown) on the right hand plunger, and appropriateshoulderson the plungers are the main springs 39 and 48, both acting to move their respective plungers in a'forward' direction. Forward of the mounting blocklt main spring plungerextensions M and 42;are secured to each main spring plunger. These plunger extensions are adapted tdserve as strikers for driving the firing -pinsandeachis provided with a depending arm respectively 63 arid-44 providing a'point of pivotal 5 attachment for rearwardly extending sears l5and 46. Thesesears extend rearwardly throughguiding and clearance apertures41 and 48 in the mounting block I 6 and are each biased to 'swing downwardly relative to" the plunger extension bya-sp'ring Ale on-the lefthand s'earand a'similar spring (not shownffor'the right'hand searQboth received in blind holes in said extensions. The rear face "of the' mounting-block is provided with a hardened sear plate" 5 l "for 'engagement by the sears 45 and "46'to hold the respective main springs in a cocked position. In position to receive the impact of "the "main spring-plunger extensions or' s'trikers there are supported 'lefthand firing pin 53a'n'd a similar right hand pin (not shown) which'pass through holes in the standing breech into position to impact uponthe-primer of a chambered shot shell. Firing pin retracting spring55 engages the left hand pin and'a similar spring "(not shown) engages the right "handpin to normally urge the'firing pins rearwardly a sufiicien't distance to prevent their protrusion from thej'face of 'the' standing breech.

"The sears are actuated to cause the desired release of one or theother of thei'mainspring plunger extensions or strikers by a'trigger l4, swingably supported on the mounting block l6, which acts through ,a disconnector "or tripper 5 6 supported'for lateral swinging movement from the -block [6. The tripper 'has'a depending arm on which there. is mounteda'rollerii'fl engaging the upper face ottheftrigger' and "centered through the spring 58 which formsi'tspivotaxle rotation of the selector to one or the other of its extreme positions will apply a spring tension tending to shift the tripper to one or the other of its extreme positions.

In either extreme position of the tripper, the pulling of the trigger 'actsthrough the roller 57 to produce a further rotation'of the-tripper 56, bringing one of the 'armst-B or'EM of the tripper into lifting engage- -ment with the rearwardly extending tail of the respective sear 45 or 46. As the sear is disengagedfrom the sear plate 5|, the plunger extension or striker drives the associated firing pin intoxthe shot'shell primer opposed thereto. :At the same time, the down-turned end 65 or'the similarfend (not shown) ofthe right hand .sear applies'the pressure of theassociated sear spring toithetripperx-in opposition to .the'force ofzthe tripper spring 58. .The forces of these springs are so balanced that upon release'of .thetrigger the sear'spring overcomes the tripper spring-and shifts the tripper: over center to v a'newfzpositi'on where a'second actuation of the trigger will release thesecon'd sear andfire the second barrel.

An involuntary release of the triggeruand an involuntary second pull duringthe interval in whichrthegun is subject to recoil is prevented by an anti-doubling-inertia plunger l5 .andits associated spring "16 acting tohold'the inertia plunger in -a normallyrear-ward position. As the gun recoils the inertia plunger tends tomaintain its original position, causing the tip-ofithe inertia plunger to come beneathlthe block of the' trigger to prevent a an involuntary release and inadvertent double firing.

When thestrikers are againcocked the tripper 56 is again .under the control of the tripper spring 58 ancl'returns to the position determined :by thesetting or the-selector "l5. Thusgit 'is'.-possibletoset the selector to f fire eitherbarrel first and at each reloading I'return without'furtl'i'er attention'to that setting,- or the ch'oice of barrels may be made and set at any time.

Cookin and automaticlsafety :Each time the actionqof .the .gun is opened .to reload :or for-any other purpose, anyrfired barrel "is coeked'andthe safety automatically moved to Safe position. Theseoperations'saresperformed by the cooking rod 61 which ishmount'ed for reciprocation in'thelframe' Land *isguided therein by:-passing[through-aligned: holes in the cocking-rod guide bushing fitpthe locking bolt l l and" by a coaxial r-e'xtension 59 'engagediwith the cockingrodby'ia "tenon'ed joint 1 and passing through a hole 'inthe mounting .b-lock' It. A cocking rod retracting spring "it-"surrounds the extensionfifi andacts betweenathe"forward'uface of the bloek. I6 andva flange l l-- on the extension to normally urge the "cockingrod-to aa forward position. 'Acpositive limit risxpla-cedi onr'forward movementby'a; snap ring i2; engaged-in" a: groove in the cooking rod shank rand brought into engagement with the rear face of -the'co cki-ng rod guide bushing 68 which passes through theiront end of 1 the frame: and athreadably engages a bore in the joint pin 5.

:Quring rearward. movement .of the cocking rod the flange 1 [engages the front face of the main spring plunger extensions 4|- and 42, moving them rearwardly into position for engagement of the sears 45 and 46 with the sear plate 5I. At the same time, the tip of the cocking rod extension 69 engages the safety control 9 and moves it rearwardly until the downward extension 13 of the safety is positioned over a block 14 on'the trigger to prevent operation thereof.

The cocking rod is reciprocated each time the action of the gun is opened as a result of the engagement of the cam 11, formed in the foreend base 23, with the forward end 18 of the cocking rod. This operation will be readily understood when it is recalled that the fore-end base is, for operating purposes, a unit with the barrels and turns with them about the axis of the joint pin each time the action is opened.

Breech locking As previously mentioned in the general discussion, the action is locked in closed position by a breech locking bolt 1 I which engages a recess 21 in the barrel lug I8 and is under the control of the top lever l0.

A top lever cam I9 is fastened by a screw or other convenient means, not shown, to the shank of thetop lever and carries a depending cam pin 80 which engages in a transverse slot 81 in the the bolt II to convert rotary motion of the top lever shank to reciprocation of the bolt. A spring and plunger, not shown, but of any convenient form, may engage an abutment on the top lever cam and thereby bias the bolt to a normally forward position.

To provide for a smoother closing movement of the action, a bolt stop 82 may be mounted in the frame and urged upwardly by a spring 83 to a position in front of the bolt II. Thus, whenever the bolt is retracted and the action opened the bolt stop springs upwardly to retain the bolt in its rearmost position, escape of the bolt stop being prevented by engagement with the cocking rod 61. As the action is closed, the lower surface of the barrel lug IB to each side of the slot 84, which provides clearance for the cocking rod, will engage the upper surface of the bolt stop and depress it to its lower position. The depression of the bolt stop 82 releases the bolt II which then snaps out to engage the recess 21 in the barrel lug. To insure a tight locking action the tip of the bolt II and the recess 21 should inter-engage on matching tapers.

Extraction and automatic ejection Extractor plungers 85 and 86 are mounted for reciprocation in parallel bores in the barrel lug I8 and are urged to a normally rearward position by a spring not shown on the left hand plunger and a similar spring 88 on the right hand plunger. Each plunger is provided with an extractor claw 89 or 90 which intersects the corresponding barrel chamber in position to engage beneath the rim ofthe head of a chambered shell. Rounded cam surfaces 9| and 92 on each extractor claw engage the standing breech as the action is closed and force the extractors back fiush with the breech end of the barrel. As the gun is opened without firing, the extractor cams again ride out on the standing breech and the unfired shells are retracted by the springs about of an inch to a position where they may be readily grasped for manual removal.

Automatic ejection is desirable to positively and completely eject any fired shells and is accomplished by setting a latch to hold the ex- 6 tractor spring tensioned when the shell is fired, and releasing this latch as a function of completion of the movement of the action to breech open position. The ejector latches 93 and 94 are each pivoted in the barrel lug l8 and the right hand latch 94 is provided with a hook 96 to engage a detent notch 98 in the extractor plunger 86. A spring-urged detent ball I00 engages holes in the latch to releasably secure the latch in either extractor holding or extractor releasing position. Similar arrangements (not shown) are provided for the left hand latch 93.

The ejector latches are moved to extractor holding position as a function of the firing of the shell by actuator pistons MI and I02 which are received in bores intersecting the chambers and provided with offset ends which pass through slots in the extractor shanks and overlie the ejector latches. The inner ends of the actuator pistons are arranged in position to contact the body paper of a chambered shell which upon firing applies a sufficient impulse to the actuator piston to trip the latch. Tests have proven that this action is quite consistent and reliable and that it does not tend to burst shell bodies or blank disks therefrom, although there is a slight localized expansion. Because of this localized expansion, extraction is facilitated by a fairly wide chamber surrounding the actuator piston bores.

As the action reaches a substantially com pletely open position, a latched extractor is tripped by the engagement of the associated ejec.. tor release rod I03 or I04 with an abutment I05 at the forward end of the frame. It will be noted that the release rods pass through the extractor springs and through the end of the extractor shank being provided with slightly enlarged portions such as I06 which will abut the end of the extractor shank at substantially the instant the release of the ejector latch is complete. In the event a shell tends to stick in the chamber and is not immediately ejected by the release of the extractor latch, the engagement of the shoulder of the release rod with the extractor shank will impart a primary extraction force sufficient to dislodge a tightly chambered shell.

Miscellaneous To cushion the shock of abruptly opening the action, a barrel cushion I08 is secured over the abutment I05 in the frame and suitably apertured to permit passage of the shanks of the ejector release rods. As the action is opened completely, this cushion is compressed between the barrel lug and the abutment I05 to prevent noise and deformation of any parts. Preferably this cushion is formed of neoprene or other oil-proof resilient material suitably cemented or vulcanized in place.

The construction and assembly of the barrels and rib have been described in sufficient detail in the general discussion but it may be well to point out that this construction makes it possible for each barrel to be absolutely symmetrical with regard to the bore axis and virtually independent of the other barrel insofar as vibration characteristics and thermal expansion rates are concerned. These factors combine to insure consistent shooting at all times and this construction is also an important feature in cost reduction.

We claim:

1. In an upward tilting breech firearm having a frame provided with a spring-urged striker, a fire control mechanism for said striker, a standing breech, and a barrel hinge pin; a barrel asamino??? 7 sembly 1tiltable:abouttsaid",hingetpir rand a looking :bolt reciprocably mounted 11in the .:standing breech for movement iintouengagement with "s the :barrel assembly to lock theibreech :end wof vsaid rbarrehassembly innengagement withi'thesstanding breech; the combination 1, comprising .-a :cocking rod a front bearingafoiusaid cocking ,TOdJlA'OllDtGd in said; hinge-pin; a rear bearing: for said cocking rod formednby a :bore passingihroughe thezlocking bolt, vsaid cocking .rod being supported tin isaid bearings :with freedom for reciprocation rnza foreend imounted onvsaid tbarrel assembly to'atilt therewith about said hinge pin; a cammounted in said fore-end and shapedto definefa portion. relatively remote lfrom said hinge pin engaging the end of said cocking rod when thebreechsend of said-barrel assembly engages the standingbreech and movablewith the barrel assembly as the same is tilted -about said hinge pin to successively "bringinto 'engagernentawith end of the cook- I ing-ro'd portions of the cam-which are progressively less remote fromthe hingepin; thereby converting tilting movement of-said barrel assembly into reciprocation of the cooking rod; and flanged means mounted directiy on the rear-end'oflsaid cocking rod and directly engageable with *the striker'to -movesame to cocked position aa'said barrel assembly is tilted.

'2. 'In'the combinationdescribedin claim 1, a

block in said frame bored to provide a bearing imahgnmentwith-saidcocking 'rod"bearingsand "rea-mvardly disposed relative thereto; coaxial extension *ofsaid'fiangewmeans =received I in-said bearing; spring"means'encirciin said "ez'ztension between saidblocic and the fianged means-urgiirg said cockingrod forwardly and asafety member movable .from :a forward position gto za 1 rearward :position in which it blocks operation :of the trigger, said asafety member *being disposed directly in the path of :said coaxial extensionand movable 1 thereby ..to :said 1 rearward position has said 1 cocking rod is v:reciprocated.

.*3. The ;,combination defined in claim '1 for use .in-;a zdoubleibarreled firearm,having itwo spring- .urgecl strikers, said cocking rod bearings being positioned :in a plane passing ;substantia11y :mid-

---way' between the-barrels and-betweenthetwoxsaid strikers; said-flangedmeans. mountedmnatne cocking rodfi'being of, suchisizeand shape as tohave substantially simultaneous direct engagement withiboth of said .istrikers ::as :the acocking .rod 1 is .;r.eciprocated.

DONALD S. FOOTE. EUGENE S. ATWELL.

"References zones .in the file of :this patent UNITED STAT-ES PATENTS l-Iorsrud. -May=22,=1945 

